US20180067218A1 - Observation system and observation method - Google Patents
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- US20180067218A1 US20180067218A1 US15/811,157 US201715811157A US2018067218A1 US 20180067218 A1 US20180067218 A1 US 20180067218A1 US 201715811157 A US201715811157 A US 201715811157A US 2018067218 A1 US2018067218 A1 US 2018067218A1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01W—METEOROLOGY
- G01W1/00—Meteorology
- G01W1/02—Instruments for indicating weather conditions by measuring two or more variables, e.g. humidity, pressure, temperature, cloud cover or wind speed
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/22—Transmitting seismic signals to recording or processing apparatus
- G01V1/223—Radioseismic systems
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/02—Generating seismic energy
- G01V1/04—Details
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/22—Transmitting seismic signals to recording or processing apparatus
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- G—PHYSICS
- G08—SIGNALLING
- G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
- G08C25/00—Arrangements for preventing or correcting errors; Monitoring arrangements
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q9/00—Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
- H04W4/30—Services specially adapted for particular environments, situations or purposes
- H04W4/38—Services specially adapted for particular environments, situations or purposes for collecting sensor information
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/16—Receiving elements for seismic signals; Arrangements or adaptations of receiving elements
- G01V1/18—Receiving elements, e.g. seismometer, geophone or torque detectors, for localised single point measurements
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L67/00—Network arrangements or protocols for supporting network services or applications
- H04L67/01—Protocols
- H04L67/12—Protocols specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2209/00—Arrangements in telecontrol or telemetry systems
- H04Q2209/20—Arrangements in telecontrol or telemetry systems using a distributed architecture
- H04Q2209/25—Arrangements in telecontrol or telemetry systems using a distributed architecture using a mesh network, e.g. a public urban network such as public lighting, bus stops or traffic lights
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2209/00—Arrangements in telecontrol or telemetry systems
- H04Q2209/40—Arrangements in telecontrol or telemetry systems using a wireless architecture
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q2209/00—Arrangements in telecontrol or telemetry systems
- H04Q2209/80—Arrangements in the sub-station, i.e. sensing device
- H04Q2209/88—Providing power supply at the sub-station
- H04Q2209/886—Providing power supply at the sub-station using energy harvesting, e.g. solar, wind or mechanical
Definitions
- a monitoring technique in which an observation apparatus gathers various types of environmental information using a wireless sensor network where a plurality of sensor nodes that perform wireless communication is arranged, has been proposed.
- the environmental information include information about temperature, humidity, soil water content, and acceleration.
- a wireless sensor network is referred to as “WSN”.
- Each sensor node of the WSN is powered by a solar battery or the like and performs measurement to obtain environmental information over a long period. This limits the amount of electric power the sensor node can use in wireless communication. For this reason, each sensor node transmits environmental information to the observation apparatus, which is distant from the sensor node, by multi-hop communication that relays the environmental information to an adjacent another sensor node rather than transmitting the environmental information directly to the observation apparatus.
- Each sensor node, for which sensing interval is set in advance, of the WSN performs measurement to obtain an environmental information unit each time the sensing interval elapses and transmits the measured environmental information unit to a parent server.
- Patent Document 1 Japanese Laid-open Patent Publication No. 2003-115092
- Patent Document 2 Japanese Laid-open Patent Publication No. 2011-013765
- Patent Document 3 Japanese Laid-open Patent Publication No. 2012-080622
- the observation apparatus fails to obtain a minimum number of environmental information units, it is difficult for the observation apparatus to conduct accurate monitoring.
- an observation system includes a plurality of nodes; and a server including: a processor that executes a process including: transmitting data to the plurality of nodes; receiving, response data from the plurality of nodes; first determining an incoming data-unit count, the incoming data-unit count being the number of response data units incoming from the plurality of nodes to the server; calculating a ratio of nodes that perform data transmission so that the server receives at least as many data units as a requested data-unit count to the plurality of nodes based on a data missing ratio and the requested data-unit count, the data missing ratio being obtained from the incoming data-unit count and a total node count, the total node count being the number of the nodes included in the system; and sending information about the ratio calculated by the calculating to the plurality of nodes, wherein, each of nodes transmits data to the server in accordance with the information about the ratio.
- FIG. 1 is a diagram illustrating an example of an observation system according to an embodiment
- FIG. 2 is a sequence diagram of the observation system
- FIG. 3 is a functional block diagram illustrating a configuration of an observation apparatus
- FIG. 4 is a functional block diagram illustrating a configuration of a node
- FIG. 5 is a flowchart illustrating a procedure for processing of the observation apparatus
- FIG. 6 is a flowchart illustrating a processing procedure for profiling
- FIG. 7 is a flowchart illustrating a processing procedure for monitoring
- FIG. 8 is a flowchart illustrating a procedure for processing of a node
- FIG. 9 is a flowchart illustrating a processing procedure for cycle measurement
- FIG. 10 is a diagram illustrating a hardware configuration of a node.
- FIG. 11 is a diagram illustrating an example of a computer that executes an observation program.
- FIG. 1 is a diagram illustrating an example of an observation system according to the embodiment.
- the observation system includes an observation apparatus 100 and nodes 10 a , 10 b , 10 c , 10 d , 10 e , 10 f , 10 g , 10 h , 10 i , and 10 j .
- the observation apparatus 100 is an example of “server”.
- the observation system may include one or more other nodes.
- the nodes 10 a to 10 j may be collectively denoted as “the nodes 10 ” as appropriate.
- Each of the nodes 10 is charged with an energy harvester or the like and executes various processing triggered by, for instance, wireless reception or sensor response.
- the node 10 wirelessly transmits an environmental information unit obtained by measurement using a sensor and other information. When a battery is depleted, the node 10 is recharged to repeatedly execute processing described above. Examples of the environmental information unit include information about temperature, humidity, soil water content, and acceleration.
- the node 10 transmits the environmental information unit and other information to the observation apparatus 100 via multi-hop communication. This limits the amount of electric power the node 10 can use in wireless transmission and, accordingly, makes a radio range of the node 10 short. For this reason, when distant from the observation apparatus 100 , the node 10 is unable to perform direct wireless communication with the observation apparatus 100 . In such a case, the node 10 transmits data to the observation apparatus 100 via multi-hop communication, in which the data is relayed via another one or more of the nodes 10 .
- data, which is destined for the observation apparatus 100 , transmitted from the node 10 j is relayed via the nodes 10 h and 10 a to reach the observation apparatus 100 .
- Data, which is destined for the node 10 j , transmitted from the observation apparatus 100 is relayed via the nodes 10 a and 10 h to reach the node 10 j.
- the node 10 In case of occurrence of data missing due to, for instance, congestion, the node 10 performs retransmission control to transmit the data again.
- the observation apparatus 100 performs profiling and monitoring. The profiling, which is to be performed by the observation apparatus 100 , is described first.
- the observation apparatus 100 transmits a “data gathering instruction” to all the nodes 10 included in the observation system. Upon receiving the data gathering instruction, each of the nodes 10 transmits a response data unit destined for the observation apparatus 100 .
- the observation apparatus 100 receives response data units from the nodes 10 and determines the number of the response data units.
- the number of the response data units is denoted as “arrived data-unit count” as appropriate.
- the observation apparatus 100 calculates a missing ratio from a total node count, which is the number of all the nodes 10 included in the observation system, and the arrived data-unit count.
- the observation apparatus 100 also calculates a measurement execution probability from the total node count, the missing ratio, and a requested data-unit count.
- the observation apparatus 100 informs all the nodes 10 included in the observation system of the measurement execution probability and proceeds to the monitoring, which is described below.
- the requested data-unit count is a value set by an administrator in advance.
- the observation apparatus 100 performs the monitoring on condition that the number of data units received from the nodes 10 be larger than or equal to the requested data-unit count.
- the measurement execution probability is a ratio of a minimum number of the nodes 10 that perform data transmission so that the observation apparatus 100 receives at least as many data units as the requested data-unit count to the number of all the nodes 10 .
- the observation apparatus 100 transmits a “cyclical data gathering instruction” to all the nodes 10 included in the observation system.
- each of the nodes 10 starts a cyclical operation.
- the node 10 generates a random variable and, when the random variable is smaller than or equal to the measurement execution probability, the node 10 transmits an environmental information unit to the observation apparatus 100 .
- the node 10 suspends transmission of the environmental information unit until another random variable is generated in the next cycle.
- the observation apparatus 100 Upon receiving environmental information units of one cycle, the observation apparatus 100 compares the number of the environmental information units of one cycle against the requested data-unit count. When the number of environmental information units is larger than or equal to the requested data-unit count, the observation apparatus 100 continues processing of receiving environmental information units transmitted every cycle. On the other hand, when the number of environmental information units is smaller than the requested data-unit count, the observation apparatus 100 proceeds to the profiling.
- FIG. 2 is a sequence diagram of the observation system.
- the nodes 10 a and 10 j are illustrated in FIG. 2 , but illustration of the other nodes 10 is omitted. A procedure for the profiling is described below.
- the observation apparatus 100 transmits the data gathering instruction to the nodes 10 (S 10 ).
- the node 10 a Upon receiving the data gathering instruction, the node 10 a transmits a response data unit to the observation apparatus 100 (S 11 ).
- the node 10 j transmits a response data unit to the observation apparatus 100 (S 12 ).
- the observation apparatus 100 Upon receiving the response data units from the nodes 10 , the observation apparatus 100 calculates a measurement execution probability (S 13 ). The observation apparatus 100 informs the nodes 10 a and 10 j of the measurement execution probability (S 14 ).
- the observation apparatus 100 transmits a cyclical data gathering instruction to the nodes 10 (S 20 ).
- the nodes 10 a and 10 j Upon receiving the cyclical data gathering instruction, the nodes 10 a and 10 j perform an operation of a cycle T 1 and an operation of a cycle T 2 .
- the cycle T 1 is described below.
- the node 10 a makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S 21 ). When the random variable is smaller than or equal to the measurement execution probability, the node 10 a performs sensing to acquire an environmental information unit (S 22 ). The node 10 a transmits the environmental information unit to the observation apparatus 100 (S 23 ).
- the node 10 j makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S 24 ). When the random variable is smaller than or equal to the measurement execution probability, the node 10 j performs sensing to acquire an environmental information unit (S 25 ). The node 10 j transmits the environmental information unit to the observation apparatus 100 (S 26 ).
- the cycle T 2 is described below.
- the node 10 a makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S 27 ). When the random variable is larger than the measurement execution probability, the node 10 a is on standby until the next cycle.
- the node 10 j makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S 28 ). When the random variable is smaller than or equal to the measurement execution probability, the node 10 j performs sensing to acquire an environmental information unit (S 29 ). The node 10 j transmits the environmental information unit to the observation apparatus 100 (S 30 ).
- the observation apparatus 100 calculates a measurement execution probability using a missing ratio of data units transmitted from all the nodes 10 and informs all the nodes 10 of the measurement execution probability.
- Each of the nodes 10 controls transmission of an environmental information unit in accordance with the informed measurement execution probability.
- occurrence of a situation where all the nodes 10 simultaneously transmit environmental information units can be at least reduced. This allows obtaining as many environmental information units as the requested data-unit count or more while preventing congestion.
- congestion is less likely to occur, data missing can be prevented, frequency of when the node 10 retransmits an environmental information unit is reduced, and reduction in power consumption can be achieved.
- FIG. 3 is a functional block diagram illustrating the configuration of the observation apparatus.
- the observation apparatus 100 includes a communication unit 110 , an input unit 120 , a display unit 130 , a storage unit 140 , and a control unit 150 .
- the communication unit 110 is a communication device that performs data communication with the nodes 10 via wireless communication.
- the control unit 150 which is described below, exchanges data with the nodes 10 via the communication unit 110 .
- the input unit 120 is an input device that inputs a variety of information to the observation apparatus 100 .
- the input device corresponds to an input device, which may be, for instance, a keyboard, a mouse, and/or a touch panel.
- the display unit 130 is a display device that displays information output from the control unit 150 .
- the display unit 130 corresponds to, for instance, a display or a touch panel.
- the storage unit 140 includes requested-data-unit-count information 141 , total-node-count information 142 , and receipt-count information 143 .
- the storage unit 140 corresponds to, for instance, a storage device, such as a semiconductor memory device, examples of which include a random access memory (RAM), a read only memory (ROM), and a flash memory.
- the requested-data-unit-count information 141 is information about the requested data-unit count that is set by the administrator or the like.
- the administrator enters the requested-data-unit-count information 141 to the observation apparatus 100 by operating the input unit 120 .
- the total-node-count information 142 is information about the total node count, which is the total number of nodes included in the observation system. For instance, the administrator that has acquired the total node count in advance may enter the total-node-count information 142 to the observation apparatus 100 by operating the input unit 120 .
- the receipt-count information 143 is information indicating a receipt count, which is the number of environmental information units received in one cycle.
- the receipt-count information 143 may hold cycle-by-cycle receipt counts of environmental information units.
- the control unit 150 includes a determining unit 151 , a calculation unit 152 , a notification unit 153 , and a judging unit 154 .
- the control unit 150 may correspond to, for instance, an integrated device, such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA).
- the control unit 150 may correspond to, for instance, an electronic circuit, such as a central processing unit (CPU) or a micro processing unit (MPU).
- the determining unit 151 is a processing unit that determines an arrived data-unit count by transmitting the data gathering instruction to the nodes 10 of the observation system and aggregating the number of response data units transmitted from the nodes 10 .
- the determining unit 151 outputs information about the arrived data-unit count to the calculation unit 152 .
- the determining unit 151 determines, as the arrived data-unit count, for instance, the number of response data units received from the nodes 10 in a fixed period of time, which corresponds to one cycle, from when the data gathering instruction is transmitted.
- the calculation unit 152 is a processing unit that calculates a missing ratio and a measurement execution probability.
- the calculation unit 152 outputs information about the measurement execution probability to the notification unit 153 . Processing, through which the calculation unit 152 calculates a missing ratio, is described below.
- the calculation unit 152 calculates a missing ratio using Equation (1).
- Equation (1) an arrived data-unit count, corresponds to the arrived data-unit count fed to the calculation unit 152 from the determining unit 151 .
- N a total node count, corresponds to the total number of nodes contained in the total-node-count information 142 .
- the calculation unit 152 calculates a measurement execution probability using Equation (2).
- Equation (2) Y, a requested data-unit count, corresponds to the requested data-unit count contained in the requested-data-unit-count information 141 .
- N the total node count, corresponds to the total node count contained in the total-node-count information 142 .
- Z the missing ratio, is the missing ratio Z calculated using Equation (1).
- ⁇ is a margin that is set by the administrator as appropriate.
- the measurement execution probability P is a value corresponding to a ratio of a minimum number of nodes that perform data transmission so that at least as many data units as the requested data-unit count are gathered to the total node count.
- the notification unit 153 is a processing unit that transmits information about the measurement execution probability to all the nodes 10 of the observation system. Upon completing transmission of the information about the measurement execution probability, the notification unit 153 outputs information indicating completion of the profiling to the judging unit 154 .
- Processing described above performed by the determining unit 151 , the calculation unit 152 , and the notification unit 153 correspond to the profiling.
- the judging unit 154 Upon receiving the information indicating completion of the profiling, the judging unit 154 starts the monitoring by transmitting the cyclical data gathering instruction to all the nodes 10 of the observation system. Each time one cycle elapses, the judging unit 154 counts a receipt count of one cycle, which is the number of environmental information units received in the one cycle, and stores the receipt count in the receipt-count information 143 . The judging unit 154 compares the receipt count of one cycle against the requested data-unit count and, when the number of the data units of one cycle is larger than or equal to the requested data-unit count, continues the monitoring.
- the judging unit 154 compares the receipt count of one cycle against the requested data-unit count and, when the number of the data units of one cycle is smaller than the requested data-unit count, the judging unit 154 issues a profiling request to the determining unit 151 , the calculation unit 152 , and the notification unit 153 again.
- the determining unit 151 Upon receiving the profiling request, the determining unit 151 , the calculation unit 152 , and the notification unit 153 perform the profiling again.
- FIG. 4 is a functional block diagram illustrating the configuration of the node.
- the node 10 includes a communication unit 11 , a sensor 12 , a battery 13 , a storage unit 14 , and a control unit 15 .
- the communication unit 11 is a processing unit that performs data communication with another node 10 and the observation apparatus 100 via wireless communication.
- the control unit 15 which is described below, exchanges data with the other node 10 and the observation apparatus 100 via the communication unit 11 .
- the sensor 12 is a sensor that performs measurement to obtain various types of environmental information. For instance, the sensor 12 measures, as environmental information, temperature, humidity, soil water content, and acceleration.
- the battery 13 is a battery to be charged using an energy harvester, such as a solar panel.
- the storage unit 14 holds environmental information 14 a , measurement-execution-probability information 14 b , and a route table 14 c .
- the storage unit 14 corresponds to, for instance, a storage device, such as a semiconductor memory device, examples of which include a RAM, a ROM, and a flash memory.
- the environmental information 14 a is environmental information obtained through measurement using the sensor 12 .
- the measurement-execution-probability information 14 b is information about the measurement execution probability informed by the observation apparatus 100 .
- the route table 14 c contains information about a route for transmitting data to a destination. For instance, the route table 14 c associates a destination with an adjacent node on a way to the destination.
- the control unit 15 includes a measurement unit 15 a and a transceiving unit 15 b .
- the control unit 15 may correspond to, for instance, an integrated device, such as an ASIC or an FPGA.
- the control unit 15 may correspond to, for instance, an electronic circuit, such as a CPU or an MPU.
- the control unit 15 performs an intermittent operation using a not-illustrated timer or the like in regular cycles that are set in advance.
- the control unit 15 may iterate a sequence, in which the control unit 15 starts the operation when a change in environmental information is detected by the sensor 12 and enters a sleep mode when a predetermined period time has elapsed since the start of the operation.
- the measurement unit 15 a is a processing unit that acquires the environmental information 14 a from the sensor 12 and stores the acquired environmental information 14 a in the storage unit 14 .
- the transceiving unit 15 b Upon receiving the data gathering instruction from the observation apparatus 100 , the transceiving unit 15 b transmits a response data unit to the observation apparatus 100 . Upon receiving the measurement-execution-probability information 14 b from the observation apparatus 100 , the transceiving unit 15 b stores the measurement-execution-probability information 14 b in the storage unit 14 .
- the transceiving unit 15 b generates a random variable, which ranges between 0 and 1, using a random function and compares the random variable against the measurement execution probability of the measurement-execution-probability information 14 b .
- the random variable is smaller than or equal to the measurement execution probability
- the transceiving unit 15 b transmits the environmental information 14 a to the observation apparatus 100 .
- the transceiving unit 15 b suspends transmission of the environmental information 14 a to the observation apparatus 100 .
- FIG. 5 is a flowchart illustrating the procedure for processing of the observation apparatus.
- the observation apparatus 100 performs the profiling (S 101 ).
- the observation apparatus 100 performs the monitoring (S 102 ).
- the observation apparatus 100 moves to S 101 .
- processing is to be ended Yes at S 103
- the observation apparatus 100 completes processing.
- FIG. 6 is a flowchart illustrating the processing procedure for the profiling.
- the determining unit 151 of the observation apparatus 100 transmits the data gathering instruction to all the nodes 10 (S 150 ) and receives response data units (S 151 ).
- the determining unit 151 determines whether the fixed period of time has elapsed (S 152 ). When the fixed period of time has not elapsed (No at S 152 ), the determining unit 151 moves to S 151 . On the other hand, when the fixed period of time has elapsed (Yes at S 152 ), the calculation unit 152 of the observation apparatus 100 calculates a measurement execution probability (S 153 ). The notification unit 153 of the observation apparatus 100 transmits the measurement execution probability to all the nodes 10 (S 154 ).
- FIG. 7 is a flowchart illustrating the processing procedure for the monitoring.
- the judging unit 154 of the observation apparatus 100 transmits the cyclical data gathering instruction to all the nodes 10 (S 161 ).
- the judging unit 154 receives environmental information units (S 162 ).
- the judging unit 154 determines whether environmental information units of one cycle have been received (S 163 ). When environmental information units of one cycle have not been received (No at S 163 ), the judging unit 154 moves to S 162 . When environmental information units of one cycle have been received (Yes at S 163 ), the judging unit 154 moves to S 164 .
- the judging unit 154 compares a receipt count against the requested data-unit count (S 164 ). When the receipt count is smaller than the requested data-unit count (Yes at S 165 ), the judging unit 154 completes the monitoring. On the other hand, when the receipt count is not smaller than the requested data-unit count (No at S 165 ), the judging unit 154 moves to S 162 .
- FIG. 8 is a flowchart illustrating the procedure for processing of the node.
- the node 10 determines whether the data gathering instruction has been received (S 201 ). When the data gathering instruction has not been received (No at S 201 ), the node 10 moves to S 201 again.
- the node 10 transmits a response data unit (S 202 ).
- the node 10 determines whether a measurement execution probability has been received (S 203 ). When a measurement execution probability has not been received (No at S 203 ), the node 10 moves to S 203 again.
- the node 10 stores the measurement execution probability (S 204 ).
- the node 10 determines whether the cyclical data gathering instruction has been received (S 205 ). When the cyclical data gathering instruction has not been received (No at S 205 ), the node 10 moves to S 205 again.
- the node 10 When the cyclical data gathering instruction has been received (Yes at S 205 ), the node 10 performs cycle measurement (S 206 ). The node 10 determines whether the data gathering instruction has been received (S 207 ). When the data gathering instruction has not been received (No at S 207 ), the node 10 moves to S 209 .
- the node 10 transmits a response data unit (S 208 ) and moves to S 209 .
- FIG. 9 is a flowchart illustrating the processing procedure for the cycle measurement.
- the node 10 determines whether a one cycle has elapsed (S 250 ). When a one cycle has not elapsed (No at S 250 ), the node 10 completes the cycle measurement.
- the node 10 when a one cycle has elapsed (Yes at S 250 ), the node 10 generates a random variable (S 251 ). When the random variable is smaller than or equal to the measurement execution probability (No at S 252 ), the node 10 transmits an environmental information unit (S 253 ) and completes the cycle measurement. When the random variable is larger than the measurement execution probability (Yes at S 252 ), the node 10 completes the cycle measurement.
- the observation apparatus 100 calculates a measurement execution probability using a missing ratio of response data units transmitted from all the nodes 10 and informs all the nodes 10 of the measurement execution probability.
- Each of the nodes 10 controls transmission of an environmental information unit in accordance with the informed measurement execution probability.
- occurrence of a situation where all the nodes 10 simultaneously transmit environmental information units to the observation apparatus 100 can be at least reduced. This allows obtaining as many environmental information units as the requested data-unit count or more while preventing congestion.
- congestion is less likely to occur, data missing can be prevented, frequency of when the node 10 retransmits an environmental information unit decreases, and reduction in electric power consumed in retransmission can be achieved.
- FIG. 10 is a diagram illustrating the hardware configuration of the node.
- the node 10 includes, for instance, a sensing device 21 , an energy harvester 22 , a battery 23 , a radio unit 24 , a power controller 25 , and a processor 26 .
- the sensing device 21 is the sensor that performs measurement to obtain environmental information.
- the energy harvester 22 is a device that generates a minute amount of electricity using, for instance, ambient radio frequency or temperature.
- the battery 23 is a battery that accumulates the electricity generated by the energy harvester 22 .
- the radio 24 is a device that performs data communication with another node.
- the power controller 25 is a device that performs power management of the node 10 .
- the processor 26 is a device that executes processing corresponding to the control unit 15 illustrated in FIG. 4 .
- FIG. 11 is a diagram describing an example of the computer that executes the observation program.
- a computer 200 includes a CPU 201 that executes various computing processing, an input device 202 that receives data entered by a user, and a display 203 .
- the computer 200 further includes a reading device 204 that reads program instructions or the like from a storage medium and an interface device 205 that transmits and receives data to and from another computer via a network.
- the computer 200 further includes a RAM 206 that temporarily stores various types of information and a storage device 207 .
- the devices 201 to 207 are connected to a bus 208 .
- the storage device 207 holds, for instance, a determining program 207 a , a calculation program 207 b , and a notification program 207 c .
- the CPU 201 reads out and loads the determining program 207 a , the calculation program 207 b , and the notification program 207 c into the RAM 206 .
- the determining program 207 a functions as a determining process 206 a .
- the calculation program 207 b functions as a calculation process 206 b .
- the notification program 207 c functions as a notification process 206 c.
- Processing of the determining process 206 a corresponds to processing of the determining unit 151 .
- Processing of the calculation process 206 b corresponds to processing of the calculation unit 152 .
- Processing of the notification process 206 c corresponds to processing of the notification unit 153 .
- the determining program 207 a , the calculation program 207 b , and the notification program 207 c are not necessarily stored in the storage device 207 in advance.
- the programs 207 a to 207 c are stored in advance in a “portable physical medium”, such as a flexible disk (FD), a compact disk read-only memory (CD-ROM), a digital versatile disc (DVD), a magneto-optical disk, or an integrated circuit (IC) card, to be inserted into the computer 200 .
- the computer 200 reads out the programs 207 a to 207 c from the physical medium and executes the programs 207 a to 207 c.
- occurrence of shortage in the number of environmental information units transmitted from sensor nodes to an observation apparatus can be at least reduced.
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Abstract
Description
- This application is a continuation of International Application No. PCT/JP2015/066407, filed on Jun. 5, 2015, the entire contents of which are incorporated herein by reference.
- The embodiment discussed herein is related to observation systems and the like.
- A monitoring technique, in which an observation apparatus gathers various types of environmental information using a wireless sensor network where a plurality of sensor nodes that perform wireless communication is arranged, has been proposed. Examples of the environmental information include information about temperature, humidity, soil water content, and acceleration. Hereinafter, a wireless sensor network is referred to as “WSN”.
- Each sensor node of the WSN is powered by a solar battery or the like and performs measurement to obtain environmental information over a long period. This limits the amount of electric power the sensor node can use in wireless communication. For this reason, each sensor node transmits environmental information to the observation apparatus, which is distant from the sensor node, by multi-hop communication that relays the environmental information to an adjacent another sensor node rather than transmitting the environmental information directly to the observation apparatus.
- Each sensor node, for which sensing interval is set in advance, of the WSN performs measurement to obtain an environmental information unit each time the sensing interval elapses and transmits the measured environmental information unit to a parent server.
- Patent Document 1: Japanese Laid-open Patent Publication No. 2003-115092
- Patent Document 2: Japanese Laid-open Patent Publication No. 2011-013765
- Patent Document 3: Japanese Laid-open Patent Publication No. 2012-080622
- However, the above-described conventional technique is disadvantageous in that shortage in the number of environmental information units transmitted from the sensor nodes to the observation apparatus can occur.
- For example, the larger the number of sensor nodes included in a WSN, the more congestion between nodes is likely to occur, which can lead to a failure of environmental information units obtained by sensor nodes through measurement to reach the parent server. When the observation apparatus fails to obtain a minimum number of environmental information units, it is difficult for the observation apparatus to conduct accurate monitoring.
- According to an aspect of an embodiment, an observation system includes a plurality of nodes; and a server including: a processor that executes a process including: transmitting data to the plurality of nodes; receiving, response data from the plurality of nodes; first determining an incoming data-unit count, the incoming data-unit count being the number of response data units incoming from the plurality of nodes to the server; calculating a ratio of nodes that perform data transmission so that the server receives at least as many data units as a requested data-unit count to the plurality of nodes based on a data missing ratio and the requested data-unit count, the data missing ratio being obtained from the incoming data-unit count and a total node count, the total node count being the number of the nodes included in the system; and sending information about the ratio calculated by the calculating to the plurality of nodes, wherein, each of nodes transmits data to the server in accordance with the information about the ratio.
- The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
- It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
-
FIG. 1 is a diagram illustrating an example of an observation system according to an embodiment; -
FIG. 2 is a sequence diagram of the observation system; -
FIG. 3 is a functional block diagram illustrating a configuration of an observation apparatus; -
FIG. 4 is a functional block diagram illustrating a configuration of a node; -
FIG. 5 is a flowchart illustrating a procedure for processing of the observation apparatus; -
FIG. 6 is a flowchart illustrating a processing procedure for profiling; -
FIG. 7 is a flowchart illustrating a processing procedure for monitoring; -
FIG. 8 is a flowchart illustrating a procedure for processing of a node; -
FIG. 9 is a flowchart illustrating a processing procedure for cycle measurement; -
FIG. 10 is a diagram illustrating a hardware configuration of a node; and -
FIG. 11 is a diagram illustrating an example of a computer that executes an observation program. - Preferred embodiments of the present invention will be explained with reference to accompanying drawings. The embodiment is not intended to limit the disclosure in any way.
-
FIG. 1 is a diagram illustrating an example of an observation system according to the embodiment. As illustrated inFIG. 1 , the observation system includes anobservation apparatus 100 andnodes observation apparatus 100 is an example of “server”. Although an example where the observation system includes thenodes 10 a to 10 j is illustrated, the observation system may include one or more other nodes. Thenodes 10 a to 10 j may be collectively denoted as “thenodes 10” as appropriate. - Each of the
nodes 10 is charged with an energy harvester or the like and executes various processing triggered by, for instance, wireless reception or sensor response. Thenode 10 wirelessly transmits an environmental information unit obtained by measurement using a sensor and other information. When a battery is depleted, thenode 10 is recharged to repeatedly execute processing described above. Examples of the environmental information unit include information about temperature, humidity, soil water content, and acceleration. - The
node 10 transmits the environmental information unit and other information to theobservation apparatus 100 via multi-hop communication. This limits the amount of electric power thenode 10 can use in wireless transmission and, accordingly, makes a radio range of thenode 10 short. For this reason, when distant from theobservation apparatus 100, thenode 10 is unable to perform direct wireless communication with theobservation apparatus 100. In such a case, thenode 10 transmits data to theobservation apparatus 100 via multi-hop communication, in which the data is relayed via another one or more of thenodes 10. - For instance, data, which is destined for the
observation apparatus 100, transmitted from thenode 10 j is relayed via thenodes observation apparatus 100. Data, which is destined for thenode 10 j, transmitted from theobservation apparatus 100 is relayed via thenodes node 10 j. - In case of occurrence of data missing due to, for instance, congestion, the
node 10 performs retransmission control to transmit the data again. - The
observation apparatus 100 performs profiling and monitoring. The profiling, which is to be performed by theobservation apparatus 100, is described first. Theobservation apparatus 100 transmits a “data gathering instruction” to all thenodes 10 included in the observation system. Upon receiving the data gathering instruction, each of thenodes 10 transmits a response data unit destined for theobservation apparatus 100. - The
observation apparatus 100 receives response data units from thenodes 10 and determines the number of the response data units. Hereinafter, the number of the response data units is denoted as “arrived data-unit count” as appropriate. Theobservation apparatus 100 calculates a missing ratio from a total node count, which is the number of all thenodes 10 included in the observation system, and the arrived data-unit count. Theobservation apparatus 100 also calculates a measurement execution probability from the total node count, the missing ratio, and a requested data-unit count. Theobservation apparatus 100 informs all thenodes 10 included in the observation system of the measurement execution probability and proceeds to the monitoring, which is described below. - The requested data-unit count is a value set by an administrator in advance. When the requested data-unit count is specified, the
observation apparatus 100 performs the monitoring on condition that the number of data units received from thenodes 10 be larger than or equal to the requested data-unit count. The measurement execution probability is a ratio of a minimum number of thenodes 10 that perform data transmission so that theobservation apparatus 100 receives at least as many data units as the requested data-unit count to the number of all thenodes 10. - Next, the monitoring, which is to be performed by the
observation apparatus 100, is described. Theobservation apparatus 100 transmits a “cyclical data gathering instruction” to all thenodes 10 included in the observation system. Upon receiving the cyclical data gathering instruction, each of thenodes 10 starts a cyclical operation. During the operation, thenode 10 generates a random variable and, when the random variable is smaller than or equal to the measurement execution probability, thenode 10 transmits an environmental information unit to theobservation apparatus 100. On the other hand, when the random variable is larger than the measurement execution probability, thenode 10 suspends transmission of the environmental information unit until another random variable is generated in the next cycle. - Upon receiving environmental information units of one cycle, the
observation apparatus 100 compares the number of the environmental information units of one cycle against the requested data-unit count. When the number of environmental information units is larger than or equal to the requested data-unit count, theobservation apparatus 100 continues processing of receiving environmental information units transmitted every cycle. On the other hand, when the number of environmental information units is smaller than the requested data-unit count, theobservation apparatus 100 proceeds to the profiling. -
FIG. 2 is a sequence diagram of the observation system. Thenodes FIG. 2 , but illustration of theother nodes 10 is omitted. A procedure for the profiling is described below. Theobservation apparatus 100 transmits the data gathering instruction to the nodes 10 (S10). Upon receiving the data gathering instruction, thenode 10 a transmits a response data unit to the observation apparatus 100 (S11). Upon receiving the data gathering instruction, thenode 10 j transmits a response data unit to the observation apparatus 100 (S12). - Upon receiving the response data units from the
nodes 10, theobservation apparatus 100 calculates a measurement execution probability (S13). Theobservation apparatus 100 informs thenodes - A procedure for the monitoring is described below. The
observation apparatus 100 transmits a cyclical data gathering instruction to the nodes 10 (S20). Upon receiving the cyclical data gathering instruction, thenodes - The cycle T1 is described below. The
node 10 a makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S21). When the random variable is smaller than or equal to the measurement execution probability, thenode 10 a performs sensing to acquire an environmental information unit (S22). Thenode 10 a transmits the environmental information unit to the observation apparatus 100 (S23). - The
node 10 j makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S24). When the random variable is smaller than or equal to the measurement execution probability, thenode 10 j performs sensing to acquire an environmental information unit (S25). Thenode 10 j transmits the environmental information unit to the observation apparatus 100 (S26). - The cycle T2 is described below. The
node 10 a makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S27). When the random variable is larger than the measurement execution probability, thenode 10 a is on standby until the next cycle. - The
node 10 j makes execution determination or, specifically, generates a random variable and compares the random variable against the measurement execution probability (S28). When the random variable is smaller than or equal to the measurement execution probability, thenode 10 j performs sensing to acquire an environmental information unit (S29). Thenode 10 j transmits the environmental information unit to the observation apparatus 100 (S30). - As described above, in the observation system according to the embodiment, the
observation apparatus 100 calculates a measurement execution probability using a missing ratio of data units transmitted from all thenodes 10 and informs all thenodes 10 of the measurement execution probability. Each of thenodes 10 controls transmission of an environmental information unit in accordance with the informed measurement execution probability. Hence, occurrence of a situation where all thenodes 10 simultaneously transmit environmental information units can be at least reduced. This allows obtaining as many environmental information units as the requested data-unit count or more while preventing congestion. Furthermore, because congestion is less likely to occur, data missing can be prevented, frequency of when thenode 10 retransmits an environmental information unit is reduced, and reduction in power consumption can be achieved. - An example of a configuration of the
observation apparatus 100 is described below.FIG. 3 is a functional block diagram illustrating the configuration of the observation apparatus. As illustrated inFIG. 3 , theobservation apparatus 100 includes a communication unit 110, aninput unit 120, adisplay unit 130, astorage unit 140, and acontrol unit 150. - The communication unit 110 is a communication device that performs data communication with the
nodes 10 via wireless communication. Thecontrol unit 150, which is described below, exchanges data with thenodes 10 via the communication unit 110. - The
input unit 120 is an input device that inputs a variety of information to theobservation apparatus 100. The input device corresponds to an input device, which may be, for instance, a keyboard, a mouse, and/or a touch panel. - The
display unit 130 is a display device that displays information output from thecontrol unit 150. Thedisplay unit 130 corresponds to, for instance, a display or a touch panel. - The
storage unit 140 includes requested-data-unit-count information 141, total-node-count information 142, and receipt-count information 143. Thestorage unit 140 corresponds to, for instance, a storage device, such as a semiconductor memory device, examples of which include a random access memory (RAM), a read only memory (ROM), and a flash memory. - The requested-data-unit-count information 141 is information about the requested data-unit count that is set by the administrator or the like. The administrator enters the requested-data-unit-count information 141 to the
observation apparatus 100 by operating theinput unit 120. - The total-node-
count information 142 is information about the total node count, which is the total number of nodes included in the observation system. For instance, the administrator that has acquired the total node count in advance may enter the total-node-count information 142 to theobservation apparatus 100 by operating theinput unit 120. - The receipt-count information 143 is information indicating a receipt count, which is the number of environmental information units received in one cycle. The receipt-count information 143 may hold cycle-by-cycle receipt counts of environmental information units.
- The
control unit 150 includes a determiningunit 151, acalculation unit 152, anotification unit 153, and ajudging unit 154. Thecontrol unit 150 may correspond to, for instance, an integrated device, such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA). Thecontrol unit 150 may correspond to, for instance, an electronic circuit, such as a central processing unit (CPU) or a micro processing unit (MPU). - The determining
unit 151 is a processing unit that determines an arrived data-unit count by transmitting the data gathering instruction to thenodes 10 of the observation system and aggregating the number of response data units transmitted from thenodes 10. The determiningunit 151 outputs information about the arrived data-unit count to thecalculation unit 152. The determiningunit 151 determines, as the arrived data-unit count, for instance, the number of response data units received from thenodes 10 in a fixed period of time, which corresponds to one cycle, from when the data gathering instruction is transmitted. - The
calculation unit 152 is a processing unit that calculates a missing ratio and a measurement execution probability. Thecalculation unit 152 outputs information about the measurement execution probability to thenotification unit 153. Processing, through which thecalculation unit 152 calculates a missing ratio, is described below. Thecalculation unit 152 calculates a missing ratio using Equation (1). In Equation (1), n, an arrived data-unit count, corresponds to the arrived data-unit count fed to thecalculation unit 152 from the determiningunit 151. N, a total node count, corresponds to the total number of nodes contained in the total-node-count information 142. -
missing ratio Z=n/N (1) - Processing, through which the
calculation unit 152 calculates a measurement execution probability, is described below. Thecalculation unit 152 calculates a measurement execution probability using Equation (2). In Equation (2), Y, a requested data-unit count, corresponds to the requested data-unit count contained in the requested-data-unit-count information 141. N, the total node count, corresponds to the total node count contained in the total-node-count information 142. Z, the missing ratio, is the missing ratio Z calculated using Equation (1). α is a margin that is set by the administrator as appropriate. -
measurement execution probability P=Y/N×(1−Z)+α (2) - In Equation (2), the measurement execution probability P is a value corresponding to a ratio of a minimum number of nodes that perform data transmission so that at least as many data units as the requested data-unit count are gathered to the total node count.
- The
notification unit 153 is a processing unit that transmits information about the measurement execution probability to all thenodes 10 of the observation system. Upon completing transmission of the information about the measurement execution probability, thenotification unit 153 outputs information indicating completion of the profiling to the judgingunit 154. - Processing described above performed by the determining
unit 151, thecalculation unit 152, and thenotification unit 153 correspond to the profiling. - Upon receiving the information indicating completion of the profiling, the judging
unit 154 starts the monitoring by transmitting the cyclical data gathering instruction to all thenodes 10 of the observation system. Each time one cycle elapses, the judgingunit 154 counts a receipt count of one cycle, which is the number of environmental information units received in the one cycle, and stores the receipt count in the receipt-count information 143. The judgingunit 154 compares the receipt count of one cycle against the requested data-unit count and, when the number of the data units of one cycle is larger than or equal to the requested data-unit count, continues the monitoring. - On the other hand, the judging
unit 154 compares the receipt count of one cycle against the requested data-unit count and, when the number of the data units of one cycle is smaller than the requested data-unit count, the judgingunit 154 issues a profiling request to the determiningunit 151, thecalculation unit 152, and thenotification unit 153 again. - Upon receiving the profiling request, the determining
unit 151, thecalculation unit 152, and thenotification unit 153 perform the profiling again. - An example of a configuration of the
node 10 is described below.FIG. 4 is a functional block diagram illustrating the configuration of the node. As illustrated inFIG. 4 , thenode 10 includes a communication unit 11, asensor 12, abattery 13, a storage unit 14, and acontrol unit 15. - The communication unit 11 is a processing unit that performs data communication with another
node 10 and theobservation apparatus 100 via wireless communication. Thecontrol unit 15, which is described below, exchanges data with theother node 10 and theobservation apparatus 100 via the communication unit 11. - The
sensor 12 is a sensor that performs measurement to obtain various types of environmental information. For instance, thesensor 12 measures, as environmental information, temperature, humidity, soil water content, and acceleration. - The
battery 13 is a battery to be charged using an energy harvester, such as a solar panel. - The storage unit 14 holds
environmental information 14 a, measurement-execution-probability information 14 b, and a route table 14 c. The storage unit 14 corresponds to, for instance, a storage device, such as a semiconductor memory device, examples of which include a RAM, a ROM, and a flash memory. - The
environmental information 14 a is environmental information obtained through measurement using thesensor 12. The measurement-execution-probability information 14 b is information about the measurement execution probability informed by theobservation apparatus 100. The route table 14 c contains information about a route for transmitting data to a destination. For instance, the route table 14 c associates a destination with an adjacent node on a way to the destination. - The
control unit 15 includes ameasurement unit 15 a and atransceiving unit 15 b. Thecontrol unit 15 may correspond to, for instance, an integrated device, such as an ASIC or an FPGA. Thecontrol unit 15 may correspond to, for instance, an electronic circuit, such as a CPU or an MPU. Thecontrol unit 15 performs an intermittent operation using a not-illustrated timer or the like in regular cycles that are set in advance. Thecontrol unit 15 may iterate a sequence, in which thecontrol unit 15 starts the operation when a change in environmental information is detected by thesensor 12 and enters a sleep mode when a predetermined period time has elapsed since the start of the operation. - The
measurement unit 15 a is a processing unit that acquires theenvironmental information 14 a from thesensor 12 and stores the acquiredenvironmental information 14 a in the storage unit 14. - Upon receiving the data gathering instruction from the
observation apparatus 100, thetransceiving unit 15 b transmits a response data unit to theobservation apparatus 100. Upon receiving the measurement-execution-probability information 14 b from theobservation apparatus 100, thetransceiving unit 15 b stores the measurement-execution-probability information 14 b in the storage unit 14. - The
transceiving unit 15 b generates a random variable, which ranges between 0 and 1, using a random function and compares the random variable against the measurement execution probability of the measurement-execution-probability information 14 b. When the random variable is smaller than or equal to the measurement execution probability, thetransceiving unit 15 b transmits theenvironmental information 14 a to theobservation apparatus 100. On the other hand, when the random variable is larger than the measurement execution probability, thetransceiving unit 15 b suspends transmission of theenvironmental information 14 a to theobservation apparatus 100. - A procedure for processing of the
observation apparatus 100 according to the embodiment is described below.FIG. 5 is a flowchart illustrating the procedure for processing of the observation apparatus. As illustrated inFIG. 5 , theobservation apparatus 100 performs the profiling (S101). Theobservation apparatus 100 performs the monitoring (S102). When processing is not to be ended (No at S103), theobservation apparatus 100 moves to S101. When processing is to be ended (Yes at S103), theobservation apparatus 100 completes processing. - A processing procedure for the profiling illustrated in S101 of
FIG. 5 is described below.FIG. 6 is a flowchart illustrating the processing procedure for the profiling. As illustrated inFIG. 6 , the determiningunit 151 of theobservation apparatus 100 transmits the data gathering instruction to all the nodes 10 (S150) and receives response data units (S151). - The determining
unit 151 determines whether the fixed period of time has elapsed (S152). When the fixed period of time has not elapsed (No at S152), the determiningunit 151 moves to S151. On the other hand, when the fixed period of time has elapsed (Yes at S152), thecalculation unit 152 of theobservation apparatus 100 calculates a measurement execution probability (S153). Thenotification unit 153 of theobservation apparatus 100 transmits the measurement execution probability to all the nodes 10 (S154). - A processing procedure for the monitoring illustrated in S102 of
FIG. 5 is described below.FIG. 7 is a flowchart illustrating the processing procedure for the monitoring. As illustrated inFIG. 7 , the judgingunit 154 of theobservation apparatus 100 transmits the cyclical data gathering instruction to all the nodes 10 (S161). - The judging
unit 154 receives environmental information units (S162). The judgingunit 154 determines whether environmental information units of one cycle have been received (S163). When environmental information units of one cycle have not been received (No at S163), the judgingunit 154 moves to S162. When environmental information units of one cycle have been received (Yes at S163), the judgingunit 154 moves to S164. - The judging
unit 154 compares a receipt count against the requested data-unit count (S164). When the receipt count is smaller than the requested data-unit count (Yes at S165), the judgingunit 154 completes the monitoring. On the other hand, when the receipt count is not smaller than the requested data-unit count (No at S165), the judgingunit 154 moves to S162. - A procedure for processing of the
node 10 is described below.FIG. 8 is a flowchart illustrating the procedure for processing of the node. As illustrated inFIG. 8 , thenode 10 determines whether the data gathering instruction has been received (S201). When the data gathering instruction has not been received (No at S201), thenode 10 moves to S201 again. - When the data gathering instruction has been received (Yes at S201), the
node 10 transmits a response data unit (S202). Thenode 10 determines whether a measurement execution probability has been received (S203). When a measurement execution probability has not been received (No at S203), thenode 10 moves to S203 again. - When a measurement execution probability has been received (Yes at S203), the
node 10 stores the measurement execution probability (S204). Thenode 10 determines whether the cyclical data gathering instruction has been received (S205). When the cyclical data gathering instruction has not been received (No at S205), thenode 10 moves to S205 again. - When the cyclical data gathering instruction has been received (Yes at S205), the
node 10 performs cycle measurement (S206). Thenode 10 determines whether the data gathering instruction has been received (S207). When the data gathering instruction has not been received (No at S207), thenode 10 moves to S209. - When the data gathering instruction has been received (Yes at S207), the
node 10 transmits a response data unit (S208) and moves to S209. - The
node 10 determines whether a measurement execution probability has been received (S209). When a measurement execution probability has not been received (No at S209), thenode 10 moves to S206. When a measurement execution probability has been received (Yes at S209), thenode 10 stores the measurement execution probability (S210) and moves to S206. - A processing procedure for the cycle measurement illustrated in S206 of
FIG. 8 is described below.FIG. 9 is a flowchart illustrating the processing procedure for the cycle measurement. As illustrated inFIG. 9 , thenode 10 determines whether a one cycle has elapsed (S250). When a one cycle has not elapsed (No at S250), thenode 10 completes the cycle measurement. - On the other hand, when a one cycle has elapsed (Yes at S250), the
node 10 generates a random variable (S251). When the random variable is smaller than or equal to the measurement execution probability (No at S252), thenode 10 transmits an environmental information unit (S253) and completes the cycle measurement. When the random variable is larger than the measurement execution probability (Yes at S252), thenode 10 completes the cycle measurement. - Advantageous effects of the observation system according to the embodiment are described below. The
observation apparatus 100 calculates a measurement execution probability using a missing ratio of response data units transmitted from all thenodes 10 and informs all thenodes 10 of the measurement execution probability. Each of thenodes 10 controls transmission of an environmental information unit in accordance with the informed measurement execution probability. Hence, occurrence of a situation where all thenodes 10 simultaneously transmit environmental information units to theobservation apparatus 100 can be at least reduced. This allows obtaining as many environmental information units as the requested data-unit count or more while preventing congestion. Furthermore, because congestion is less likely to occur, data missing can be prevented, frequency of when thenode 10 retransmits an environmental information unit decreases, and reduction in electric power consumed in retransmission can be achieved. - An example of a hardware configuration of the
node 10 is described below.FIG. 10 is a diagram illustrating the hardware configuration of the node. Thenode 10 includes, for instance, asensing device 21, an energy harvester 22, abattery 23, a radio unit 24, apower controller 25, and a processor 26. - The
sensing device 21 is the sensor that performs measurement to obtain environmental information. The energy harvester 22 is a device that generates a minute amount of electricity using, for instance, ambient radio frequency or temperature. Thebattery 23 is a battery that accumulates the electricity generated by the energy harvester 22. The radio 24 is a device that performs data communication with another node. Thepower controller 25 is a device that performs power management of thenode 10. The processor 26 is a device that executes processing corresponding to thecontrol unit 15 illustrated inFIG. 4 . - An example of a computer that executes observation program instructions (hereinafter, “program”) that implement functions similar to those of the
observation apparatus 100 presented in the above-described embodiment is described below.FIG. 11 is a diagram describing an example of the computer that executes the observation program. - As illustrated in
FIG. 11 , acomputer 200 includes aCPU 201 that executes various computing processing, aninput device 202 that receives data entered by a user, and adisplay 203. Thecomputer 200 further includes areading device 204 that reads program instructions or the like from a storage medium and aninterface device 205 that transmits and receives data to and from another computer via a network. Thecomputer 200 further includes aRAM 206 that temporarily stores various types of information and astorage device 207. Thedevices 201 to 207 are connected to abus 208. - The
storage device 207 holds, for instance, a determiningprogram 207 a, acalculation program 207 b, and anotification program 207 c. TheCPU 201 reads out and loads the determiningprogram 207 a, thecalculation program 207 b, and thenotification program 207 c into theRAM 206. The determiningprogram 207 a functions as a determiningprocess 206 a. Thecalculation program 207 b functions as acalculation process 206 b. Thenotification program 207 c functions as anotification process 206 c. - Processing of the determining
process 206 a corresponds to processing of the determiningunit 151. Processing of thecalculation process 206 b corresponds to processing of thecalculation unit 152. Processing of thenotification process 206 c corresponds to processing of thenotification unit 153. - The determining
program 207 a, thecalculation program 207 b, and thenotification program 207 c are not necessarily stored in thestorage device 207 in advance. For instance, the following configuration may alternatively be employed. Theprograms 207 a to 207 c are stored in advance in a “portable physical medium”, such as a flexible disk (FD), a compact disk read-only memory (CD-ROM), a digital versatile disc (DVD), a magneto-optical disk, or an integrated circuit (IC) card, to be inserted into thecomputer 200. Thecomputer 200 reads out theprograms 207 a to 207 c from the physical medium and executes theprograms 207 a to 207 c. - According to the embodiment, occurrence of shortage in the number of environmental information units transmitted from sensor nodes to an observation apparatus can be at least reduced.
- All examples and conditional language recited herein are intended for pedagogical purposes of aiding the reader in understanding the invention and the concepts contributed by the inventor to further the art, and are not to be construed as limitations to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiment of the present invention has been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
Claims (5)
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112180428A (en) * | 2019-07-03 | 2021-01-05 | 中国石油天然气集团有限公司 | Push-pull type observation system receiving relation generation method and device |
US20220028276A1 (en) * | 2017-01-31 | 2022-01-27 | Volkswagen Aktiengesellschaft | Method for a transportation vehicle of a transportation vehicle fleet for transmitting data to a data processing system, method for a data processing system for transmitting data of a transportation vehicle fleet to the data processing system, and transportation vehicle |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6357255B1 (en) * | 2017-03-16 | 2018-07-11 | ソフトバンク株式会社 | system |
EP3598407B1 (en) * | 2017-03-16 | 2023-07-12 | Softbank Corp. | System |
CN107271133B (en) * | 2017-06-19 | 2019-06-21 | 深圳市海纳微传感器技术有限公司 | A kind of dust storm monitoring system based on wireless sensor network |
CN110673201B (en) * | 2019-09-12 | 2022-03-08 | 吉林大学 | Low-power-consumption wired seismograph based on single-chip FPGA and high-speed ad hoc network method thereof |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050281209A1 (en) * | 2004-06-22 | 2005-12-22 | Zhijun Cai | Method for radio bearer optimization through an adaptive access probability factor |
US20100195515A1 (en) * | 2009-02-03 | 2010-08-05 | Institute For Information Industry | Node apparatus, node quantity adjustment method, and tangible machine-readable medium for a sensor network |
US20130127981A1 (en) * | 2011-05-17 | 2013-05-23 | Yale University | Efficiently distributing video content using a combination of a peer-to-peer network and a content distribution network |
US20150177399A1 (en) * | 2013-12-20 | 2015-06-25 | Sercel | Method for downloading data to a central unit in a seismic data acquisition system |
US20150223093A1 (en) * | 2012-08-17 | 2015-08-06 | China Academy Of Telecommunications Technology | Layer 2 measurement and result processing method and device under heterogeneous network |
US9413542B2 (en) * | 2013-08-07 | 2016-08-09 | Ab Initio Technology Llc | Managing data feeds |
US9582557B2 (en) * | 2013-01-22 | 2017-02-28 | Splunk Inc. | Sampling events for rule creation with process selection |
US20170105178A1 (en) * | 2015-05-04 | 2017-04-13 | Telefonaktiebolaget Lm Ericsson (Publ) | Coordinated Duty Cycle Assignment in Mesh Networks |
US20170146675A1 (en) * | 2014-07-08 | 2017-05-25 | Cgg Services Sas | System and method for reconstructing seismic data generated by a sparse spectrum emission |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5880796A (en) * | 1981-11-05 | 1983-05-14 | 三菱電機株式会社 | Telemeter poling system |
US8542763B2 (en) * | 2004-04-02 | 2013-09-24 | Rearden, Llc | Systems and methods to coordinate transmissions in distributed wireless systems via user clustering |
JP5143537B2 (en) * | 2007-12-05 | 2013-02-13 | 関西電力株式会社 | Wireless communication system |
JP5097631B2 (en) * | 2008-07-10 | 2012-12-12 | 日立Geニュークリア・エナジー株式会社 | Communication control method and sensor network system |
JP5075762B2 (en) * | 2008-08-25 | 2012-11-21 | 日立Geニュークリア・エナジー株式会社 | Sensor node and sensor network system |
TWI378685B (en) * | 2009-03-11 | 2012-12-01 | Univ Nat Sun Yat Sen | Sensor-fault detection method and wireless detection method for wireless sensor networks system |
-
2015
- 2015-06-05 JP JP2017521482A patent/JP6447723B2/en active Active
- 2015-06-05 WO PCT/JP2015/066407 patent/WO2016194235A1/en active Application Filing
-
2016
- 2016-03-24 TW TW105109165A patent/TWI616854B/en not_active IP Right Cessation
-
2017
- 2017-11-13 US US15/811,157 patent/US20180067218A1/en not_active Abandoned
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050281209A1 (en) * | 2004-06-22 | 2005-12-22 | Zhijun Cai | Method for radio bearer optimization through an adaptive access probability factor |
US20100195515A1 (en) * | 2009-02-03 | 2010-08-05 | Institute For Information Industry | Node apparatus, node quantity adjustment method, and tangible machine-readable medium for a sensor network |
US20130127981A1 (en) * | 2011-05-17 | 2013-05-23 | Yale University | Efficiently distributing video content using a combination of a peer-to-peer network and a content distribution network |
US20150223093A1 (en) * | 2012-08-17 | 2015-08-06 | China Academy Of Telecommunications Technology | Layer 2 measurement and result processing method and device under heterogeneous network |
US9582557B2 (en) * | 2013-01-22 | 2017-02-28 | Splunk Inc. | Sampling events for rule creation with process selection |
US9413542B2 (en) * | 2013-08-07 | 2016-08-09 | Ab Initio Technology Llc | Managing data feeds |
US20150177399A1 (en) * | 2013-12-20 | 2015-06-25 | Sercel | Method for downloading data to a central unit in a seismic data acquisition system |
US20170146675A1 (en) * | 2014-07-08 | 2017-05-25 | Cgg Services Sas | System and method for reconstructing seismic data generated by a sparse spectrum emission |
US20170105178A1 (en) * | 2015-05-04 | 2017-04-13 | Telefonaktiebolaget Lm Ericsson (Publ) | Coordinated Duty Cycle Assignment in Mesh Networks |
US10070388B2 (en) * | 2015-05-04 | 2018-09-04 | Telefonaktiebolaget Lm Ericsson (Publ) | Coordinated duty cycle assignment in mesh networks |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20220028276A1 (en) * | 2017-01-31 | 2022-01-27 | Volkswagen Aktiengesellschaft | Method for a transportation vehicle of a transportation vehicle fleet for transmitting data to a data processing system, method for a data processing system for transmitting data of a transportation vehicle fleet to the data processing system, and transportation vehicle |
US11971495B2 (en) * | 2017-01-31 | 2024-04-30 | Volkswagen Aktiengesellschaft | Method for a transportation vehicle of a transportation vehicle fleet for transmitting data to a data processing system, method for a data processing system for transmitting data of a transportation vehicle fleet to the data processing system, and transportation vehicle |
CN112180428A (en) * | 2019-07-03 | 2021-01-05 | 中国石油天然气集团有限公司 | Push-pull type observation system receiving relation generation method and device |
Also Published As
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TWI616854B (en) | 2018-03-01 |
JP6447723B2 (en) | 2019-01-09 |
WO2016194235A1 (en) | 2016-12-08 |
JPWO2016194235A1 (en) | 2018-03-08 |
TW201711006A (en) | 2017-03-16 |
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